Study Shows Why Woman Have Harder Time Losing Weight

Personal trainer Dawn Celapino sees a lot of women give up on exercise too quickly.

"And if people don't see results like say within the first couple weeks and they're like I'm not losing any weight and I'm doing all this stuff and I'm not losing weight, then they stop," she said.

Researchers are beginning to understand why women who work out can still have trouble losing weight.

They say exercise sets in motion various hormones that make you want to eat, which affects women most, because a woman's metabolism is almost a third slower than a man's.

"So little changes like wanting to eat more from exercise would be enough to slow their weight loss and they might not be happy," said Dr. Ken Fujioka, an endocrinologist.

He says science is now showing what to do about it, "So if you really want to lose weight or maintain a lower weight with exercise, you really have to push the heart rate up, get it up there to round 85 percent of maximum which is high."

Fujioka and Celapino agree: Most women just aren't working out hard enough.

"I see women in the gym talking to their friends, lifting five pounds. If you can walk on a treadmill or you can walk on a stairmaster and read a book, you're not working out hard enough," Celapino said

And Fujioka said if you take walks for exercise, you'd better find some hills. Celapino prefers interval training to get your heart rate up high enough.

The other key thing is no surprise: Eat healthy. If you do, Fujioka said you'll actually be satisfied quicker, even if exercise is making you hungrier.